Stem and Leaf Plot

The stem-leaf plot is drawn in two columns separated by a vertical line. The number on the left hand side of the line represents the stem and the digit(s) on the right hand side represent(s) the leaf (leaves).

Example:

Consider the following data:

40, 42, 45, 49, 51, 54, 57, 58, 60, 63, 66, 66

Since the data is in ascending order, there is no need to sort again.

We observe that there are entries with 4, 5 and 6 in the ten’s place.

Þ 4, 5 and 6 become the stems.

Let us plot the stem and leaf as follows

4 | 0 2 5 9

5 | 1 4 7 8

6 | 0 3 6 6

• Here the leaves are from the unit’s place of the entries and the stems are from the ten’s place of the given entries.
• Repeated entries too, must be considered for plotting the leaves, as in the case of 66.
• Data should be represented in numerical order, and therefore it is best to sort the data before constructing the stem and leaf plot

Try these questions :

1. The number of digit(s) in a leaf in a stem-leaf plot is
   1. Two digits
   2. One digit
   3. Three digits
   4. Five digits
   Answer : B
   There is always one digit as this represents the tens of each number.


2. Which data set was the following stem and leaf plot taken from?
   2 | 1 4 7 9
   4 | 3 6 8 9
   5 | 2 2 2 2
   a. 21479, 43689, 52222
   b. 21,479, 43, 689, 52, 222
   c. 21, 24, 27, 29, 43, 46, 48, 49, 52, 52, 52, 52
   d. 21, 24, 27, 29, 43, 46, 48, 49, 52
   Answer: C
   The stem represents the tens values, whilst each leaf is a unit value of the data set. Every value must be shown, therefore there were 4 lots of 52 recorded.